Visual and aural user interface for an automated external defibrillator

ABSTRACT

A method for operating a defibrillator including an aural output device includes causing the output device to deliver a first verbal instruction which includes a prompt to call an emergency response system; determining if the user elects to have the defibrillator continue on to a second instruction; and if it is determined that the user elects to have the defibrillator continue on to the next instruction, causing the defibrillator to deliver the second verbal instruction. In an exemplary embodiment, the step of determining if the user elects to continue on to the second instruction includes the step of determining if the user has performed an action upon the defibrillator.

CROSS-REFERENCES TO RELATED APPLICATIONS

This is a continuation of pending U.S. patent application Ser. No.10/754,338, filed Jan. 9, 2004, which is a continuation of U.S. patentapplication Ser. No. 09/972,028, filed Oct. 4, 2001 (issued as U.S. Pat.No. 6,697,671), which is a continuation of U.S. patent application Ser.No. 09/444,037, filed Nov. 19, 1999 (issued as U.S. Pat. No. 6,334,070),and also claims the benefit of provisional application No. 60/109,168filed on Nov. 20, 1998.

FIELD OF THE INVENTION

This invention relates generally to defibrillators, and morespecifically to portable, automated external defibrillators having auser interface for automatically providing an untrained rescuer withvisual and aural instructions for performing emergency cardiopulmonaryresuscitation and defibrillation therapy.

BACKGROUND OF THE INVENTION

The probability of surviving a heart attack depends on the speed withwhich appropriate medical care is provided to the person experiencingthe heart attack. To decrease the response time to a patient suffering aheart attack, it has been recognized that those persons who aretypically first to arrive at the scene of a medical emergency, includingmedical technicians (EMTs), firefighters, police and the public(hereinafter collectively referred to as “first responders”) should beprovided with portable, automated external defibrillators (AEDs). Afirst responder equipped with an AED will have a greater likelihood ofsuccessfully treating the patient than those who arrive later at thescene. An AED designed for first responder use would therefore improvethe overall success rate of treating heart attack patients.

Because the probability of surviving a heart attack depends on the speedwith which appropriate medical care is provided to the patient, theAmerican Heart Association (AHA) promotes the following “Chain ofSurvival” guidelines:

-   -   (1) Early access to emergency medical service (EMS), such as by        activating an emergency response system;    -   (2) Early CPR initiated by a rescuer to help the patient survive        until more advanced care arrives;    -   (3) Early defibrillation; and    -   (4) Early application of advanced cardiac life support (ACLS),        such as airway management, drugs, etc.

With the exception of item number 4, all of the above guidelines can beperformed by a first responder with minimal or no training, if providedwith sufficient instruction while at the scene.

Even if the first responder does have some basic training in deviceoperation and cardiopulmonary resuscitation (CPR), he or she may forgetthis basic training during the stress of reacting to a heart attack.With wider deployment of AEDs in homes and public venues, the minimallytrained or even untrained use of defibrillation devices will increase.Although some devices already exist for providing CPR prompting andautomatic defibrillation therapy, these devices rely on several hours oftraining experience and verbal cueing for the rescuer to follow. Inaddition, visual prompting of CPR and defibrillation instructions isachieved only through readable text prompts. Success is diminished dueto having to rely on memory recall of CPR and other training protocols.Even retraining and certification every two years is inadequate toensure proper administration of CPR and defibrillation therapy.

Consequently, a defibrillator is needed which is capable of successfullydirecting precise instructions to a first responder with minimal or notraining through a cardiorespiratory event, i.e., CPR as well as AEDdevice operation, by use of visual and aural instructions. Thedefibrillator should be as simple and user friendly as possible so as toremove any impediment to use by a rescuer with minimal or no training.Further, the defibrillator should be programmable so as to comply withany changes in the standard protocols for CPR and AED operation.

BRIEF SUMMARY OF THE INVENTION

In accordance with the present invention, a method for operating adefibrillator including includes causing the output device to deliver afirst verbal instruction which includes a prompt to call an emergencyresponse system; determining if the user elects to have thedefibrillator continue on to a second instruction; and if it isdetermined that the user elects to have the defibrillator continue on tothe next instruction, causing the defibrillator to deliver the secondverbal instruction. In an exemplary embodiment, the step of determiningif the user elects to continue on to the second instruction includes thestep of determining if the user has performed an action upon thedefibrillator. This action may include, for example, pressing a button.In an exemplary embodiment user input mechanism may enable the user toskip or repeat instructions. The user input mechanism may be a voicerecognition module or a user activated switch or actuator.

In accordance with further aspects of the invention, the method ofoperating a defibrillator may include causing the aural output device todeliver CPR instructions. These may include, for example, instructionsto deliver an appropriate number of breaths and chest compressions to apatient.

In accordance with yet other aspects of the present invention, a methodand a computer-executable user interface component are described whichprovide instructions to a user operating the defibrillator.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated as the same become betterunderstood by reference to the following detailed description, whentaken in conjunction with the accompanying drawings, wherein:

FIG. 1A is an isometric view of an AED having a user interface whichautomatically provides a rescuer with visual and aural instructions fordelivering CPR and/or defibrillation therapy, that is formed inaccordance with one actual embodiment of the present invention;

FIG. 1B a top level view of an AED having a user interface formed inaccordance with an alternative embodiment of the present invention;

FIG. 2 is a schematic block diagram of several of the key components ofthe AEDs shown in FIGS. 1A and 1B;

FIG. 3 a flow chart illustrating the logic used by a user interfaceprogram executed by the AED shown in FIG. 1A to provide the rescuer withvisual and aural instructions for delivering CPR and/or defibrillationtherapy;

FIG. 4 is a flow chart illustrating the logic used by the user interfaceprogram to instruct the rescuer to notify an emergency response system;

FIG. 5 is a flow chart illustrating the logic used by the user interfaceprogram to cause the AED to notify an emergency response system;

FIG. 6 is a flow chart illustrating the logic used by the user interfaceprogram to instruct the rescuer to assess the patient's condition;

FIG. 7 is a flow chart illustrating the logic used by the user interfaceprogram to instruct the rescuer to attach the AED electrodes to thepatient;

FIGS. 8A and 8B are a flow chart illustrating the logic used by userinterface program to instruct the user to operate the AED and deliverdefibrillation therapy, if necessary;

FIG. 9 is a flow chart illustrating the logic used by the user interfaceprogram to instruct the rescuer to deliver CPR; and

FIGS. 10A-10J illustrate a number of visual instructions provided by theAED in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 depicts a portable, automated external defibrillator (AED) 10formed in accordance with one actual embodiment of the present inventionand designed for use by a first responder or rescuer during a medicalemergency. The AED 10 stores electric charge and delivers the electriccharge to a patient in the form of an electric current pulse, i.e., adefibrillation pulse. The defibrillation pulse is applied to the patientvia a set of electrodes 16 if the patient is experiencing a shockableheart rhythm, such as ventricular fibrillation. In the actual embodimentof the present invention depicted in FIG. 1A, the defibrillator 10guides a rescuer with minimal training or no training whatsoever throughoperation of the AED and application of CPR and defibrillation therapyto the patient by displaying a series of visual instructions on a liquidcrystal display (LCD) 14 and by providing additional aural instructionsvia a speaker 18. In the actual embodiment of the present inventiondepicted in FIG. 1A, the rescuer merely needs to press a start button 12to initiate operation of the defibrillator, and hence, begin CPR anddefibrillation instruction.

FIG. 1B illustrates an AED 10′ formed in accordance with another actualembodiment of the present invention. In this embodiment, the display 14′comprises a number of illustrations 17 fixed to the top surface of theAED 10′ and a light-emitting diode (LED) 15 corresponding to each visualillustration 17. Accordingly, as the rescuer is instructed to performcertain actions, the LED 15 beneath the visual illustration of thataction is illuminated. For example, when the rescuer is instructed tocheck the patient's breathing, the LED 15 a beneath the visualillustration of the check breathing instruction 17 a is illuminated. Inyet another actual embodiment of the present invention, the visualinstructions for AED operation and CPR are provided on a laminated cardor flip chart, which accompany the AED. In such an embodiment, therescuer would rely more heavily on the aural instructions generated bythe AED via the speaker 18 while following visual instructions along onthe card or chart. AED 10′ also includes a shock button 11′ and startbutton 12′.

Now that the overall design of an AED capable of providing both visualand aural CPR and defibrillation instructions has been discussed,several key AED components will be discussed in more detail. However,since the components of both AED 10 and AED 10′ are essentially thesame, the description of these components will be made with reference toAED 10 as depicted in FIG. 1A.

As shown in more detail in FIG. 2, the AED 10 includes a microprocessor24 which controls the operation of the AED 10. The microprocessor 24 isconnected to the display 14 (or LEDs 15 of AED 10′), the speaker 18, thestart button 12, and the shock button 11. The microprocessor 24 is alsoconnected to a memory 20 which stores a user interface program 22 formedin accordance with the present invention to generate the visualinstructions upon the display 14 (or illuminates the LEDs 15 of AED 10′)and any accompanying aural instructions transmitted via the speaker 18.In yet other embodiments of the present invention, the memory stores avoice recognition software module which allows the rescuer to operatethe AED 10 and respond to visual and/or aural instructions via voicecommand rather than using the start and shock buttons. Such a module incombination with a microphone would then provide the rescuer withhands-free operation of the AED 10.

During defibrillation operation, the microprocessor 24 analyzes anelectrocardiogram (ECG) of a patient using an automatic heart rhythmdetection algorithm also stored in memory 20 to identify whether thepatient is experiencing a shockable heart rhythm, such as ventricularfibrillation. The detection algorithm executed by the microprocessor 24in the actual embodiment of the present invention described herein issimilar to that used in the LIFEPAK® 500 defibrillator provided byMedtronic Physio-Control Corp. of Redmond, Wash. Other known heartrhythm detection algorithms may also be used without departing from thescope of the present invention, such as those algorithms designed tocomply with standards promulgated by the Association for the Advancementof Medical Instruments (AAMI). The ECG signals analyzed by the detectionalgorithm are collected by the electrode 16 and passed through a monitorcircuit 28 to an analog-to-digital converter 26. The analog-to-digitalconverter 26 then passes the digitized signals to microprocessor 24. Ifthe microprocessor 24 detects a shockable rhythm, the microprocessorcauses a charging circuit 30 to generate a current causing a storagecapacitor (not shown) to charge in preparation for delivery of adefibrillation pulse. When the capacitor is fully charged, and deliveryof the defibrillation pulse initiated, a discharge circuit 32 coupled tothe microprocessor 24 and charge circuit 30 discharges thedefibrillation pulse to the electrodes 16 for application of thedefibrillation pulse to the patient.

In accordance with the present invention, the AED 10 will provide visualand aural instructions to the rescuer via the display 14 and the speaker18, respectively, advising application of a defibrillation pulse, inwhich case the rescuer would press a shock button 11 to deliver thedefibrillation pulse. However, in another embodiment of the presentinvention, the AED will automatically apply a defibrillation pulse tothe patient if the patient is experiencing ventricular fibrillation,without the rescuer's intervention.

Although the above describes the application of defibrillation therapyto a patient by the AED 10, the AED of the present invention actuallyprovides the rescuer with an intuitive user interface for administeringvisual and aural instructions necessary for operating the defibrillatorto provide defibrillation therapy, as well as instructions foradministering CPR. The visual instructions may include inter aliaanimated or graphic illustrations that flash, move or remain static,textual prompts, light emissions, etc, while the aural instructions mayinclude inter alia verbal prompts audible tones, etc. On a macro level,the user interface can be considered to include the user interfaceprogram 22, the display 14 or any other visual output device, generatoror mechanism, and the speaker 18 or any other aural output device,generator or mechanism. The user interface of the present invention mayalso include various user input devices or mechanisms, e.g., shockbutton 11, start button 12, or voice recognition for allowing therescuer to input information and/or commands. Since the visual and auraloutput devices, i.e., display 14 and speaker 18, have already beendescribed, the user interface program 22 of the present invention willbe described in more detail in connection with FIGS. 3-9.

FIG. 3 illustrates the logic of the user interface program 22 which isexecuted by the microprocessor 24 of the AED 10 to provide the rescuerwith visual and aural instructions via the display 14 and speaker 18. Inorder to more fully appreciate the circumstances under which the AED 10would be used and the advantages of providing a rescuer with visual andaural instructions for providing defibrillation operation/therapy andCPR, it is necessary to discuss the conditions under which the AED 10would be deployed. Typically, a rescuer would witness or encounter apatient who has collapsed or exhibited some other symptoms associatedwith cardiac arrest. The rescuer may then attempt to assess the patientand/or call for help, e.g., by calling 911. If available, the rescuerwould retrieve the AED 10 and power it on. As described above, the AED10 is turned on by pressing the start button 12. However, as also notedabove, the AED 10 may be powered on by some alternative mechanism ormethod. It will be appreciated that when the AED 10 is activated, theuser interface program 22 is initiated and proceeds as shown in FIG. 3.

The logic begins in FIG. 3 in a block 100 and proceeds to a block 102where it triggers the device to issue an aural power-on indication tothe user via the speaker 18, e.g., a power-on tone or perhaps a voiceprompt saying “Power On.” In addition, a visual power-on indicator isissued on the display 14. This could include a textual “power-on” prompton the display 14 or the illumination of an LED. Next, in a block 104,the rescuer is instructed both visually and aurally to check thepatient's responsiveness. For example, a visual instruction as shown inFIG. 10A is generated upon the LCD 14 of the AED 10. Simultaneously, therescuer is issued a verbal instruction via the speaker 18 to “Shake andShout” the patient and ask “Are You Okay?”

In addition to providing the visual and verbal instructions to check thepatient's responsiveness, the user interface program 22 also causes thestart button 12 to flash so as to indicate to the rescuer that he or shemay press the start button 12 to proceed to the next instruction. Theuser interface program 22 may further provide a verbal instruction to“Press Start Button to Continue” via the speaker 18.

Accordingly, in a decision block 106, the user interface programdetermines if the rescuer has elected to continue to the nextinstruction. In accordance with the present invention, the rescuer maycontinue to the next instruction, and hence, effect the sequence ofinstructions generated by the user interface program 22 by pressing thestart button 12 a single time. If the rescuer has not pressed the startbutton 12 to indicate his or her desire to skip to the next instruction,the logic proceeds from decision block 106 to a decision block 108 whereit determines if the rescuer's time interval for taking action andcontinuing to the next instruction has expired. If such time intervalhas not expired, the logic will merely repeat decision blocks 106 and108 until the rescuer either presses the start button 12 to continue tothe next instruction or until the rescuer action interval expires andthe user interface program 22 proceeds to the next instructionautomatically without further rescuer intervention.

It will be appreciated by those of ordinary skill in the art that theuser interface program 22 may provide the rescuer with the option ofcontinuing to the next instruction by pressing the start button 12 (orby activating some other user input mechanism or device such as anotherbutton or a voice command) or by waiting to time-out to the nextinstruction at any appropriate point during the user interface program22 or any of its subroutines. However, in an effort to avoid redundancy,decision blocks corresponding to 106 and 108 of FIG. 3 are not repeatedin the remaining figures after every such instruction. In addition, itwill be appreciated that whenever the rescuer is given the option tocontinue to the next instruction, a verbal instruction to “Press StartButton to Continue” may be issued via the speaker 18, and the startbutton 12 may be made to flash. In yet other embodiments of the presentinvention, the rescuer is not provided the option of continuing to thenext instruction on demand. Rather, some or all of the subsequentinstructions are generated on a time-out basis. Such an embodiment maybe advantageous if completely hands-free operation of the AED 10 orfurther simplification of the user interface (e.g., elimination of thestart and shock buttons) is desired.

Returning to decision blocks 106 and 108, if either is positive, thelogic will proceed to a block 10 where an emergency notificationsequence is initiated by the user interface program 22. As will bedescribed in more detail below, the emergency notification sequence is asubroutine performed by the user interface program 22 to notify theappropriate emergency response system of the patient's collapse.

In one actual embodiment of the present invention, the rescuer isinstructed by the user interface program 22 to notify the appropriateemergency response system. As will be described in more detail below, inother actual embodiments of the present invention, the AED 10 isprogrammed to notify the appropriate emergency response system directly.The rescuer initiated emergency notification sequence is depicted inmore detail in FIG. 4. The logic begins in FIG. 4 in a block 130 andproceeds to a block 132 where the rescuer is instructed via the display14 of the defibrillator to call an emergency response system telephonenumber, such as 911. In the actual embodiment of the present inventiondescribed herein, a visual instruction to call 911 as shown in FIG. 10Bis generated on the display 14 of the AED 10. A verbal instruction to“Call 911” is simultaneously generated by the speaker 18. Next, in adecision block 134, the user interface program 22 determines if therescuer has pressed the flashing start button 12 to continue to the nextinstruction. If not, the logic proceeds to a decision block 136 where itdetermines if the rescuer's interval for notifying the emergencyresponse system has expired. As noted above, the user interface program22 will proceed to the next instruction either after the rescuer pressesthe flashing start button 12 or after the rescuer action intervalexpires. Consequently, when either of these conditions occurs, the logicin FIG. 4 proceeds to a block 138 and returns to the main user interfaceprogram 22 depicted in FIG. 3 so as to proceed to the next instructionfor positioning the patient in a block 112.

In another actual embodiment of the present invention, the AED 10 isprogrammed to notify the emergency response system itself, without humanintervention. To do so, those of ordinary skill in the art willrecognize that the AED 10 must be equipped with the necessary externalinterface to communicate with the remote emergency response system. Forexample, the AED 10 may communicate with the emergency response systemvia a wireless communication link in which case the external interfaceof the AED 10 may include an antenna and transceiver for transmittingand receiving radio signals. If communicating via a “wired”communication link, e.g., a “wired” network, a remote telephone/modeconnection, a direct port-to-port connection, etc., the AED 10 will beequipped with the appropriate external interface including the necessarycircuitry for connecting to the wired communication link and thenecessary software for communicating via the appropriate networkprotocol.

The device initiated emergency notification sequence performed by theuser interface program 22 is shown in more detail in FIG. 5. Those ofordinary skill in the art will appreciate that in the actual embodimentof the present invention described herein, the device initiatedemergency notification sequence is performed as a parallel processingthread to the main user interface program 22. Consequently, the deviceinitiated emergency notification sequence will be performed and theappropriate emergency response system notified while the user interfaceprogram 22 continues to provide the rescuer with visual and aural CPRand defibrillation instructions. Accordingly, any visual or auralinstructions generated by the device initiated emergency notificationsequence will interrupt any currently generated visual or auralinstructions provided by the main user interface program 22.

Returning to the substance of FIG. 5, the device initiated emergencynotification sequence begins in a block 140 and proceeds to a block 142where the AED 10 automatically dials a preprogrammed telephone numberfor the emergency response system, e.g., 911. Accordingly, in a block144, the user interface program 22 issues via the speaker 18 a verbalinstruction confirming that “Emergency Number Called.” In addition, avisual, textual instruction of similar nature is generated on thedisplay 14 of the AED 10. Next, in a decision 146 the logic determinesif emergency notification has been completed, i.e., that the AED 10 hassuccessfully made a connection with the emergency response system andtransmitted preprogrammed information regarding its location to theemergency response system. If emergency notification has not beencompleted, the logic proceeds to a decision block 148 where itdetermines if the interval for completing the emergency notification hasexpired. If not, blocks 146 and 148 are repeated until either theemergency notification has been successfully completed or the emergencycall interval has expired.

Once emergency notification has been completed, the logic proceeds fromdecision block 146 to a block 150 where a verbal instruction is issuedvia the speaker 18 confirming that “Emergency Notification Complete.” Inaddition, a textual instruction of similar nature is generated on thedisplay 14 of the AED 10. The logic then ends in a block 154. Ifemergency notification has not been completed by the AED 10 and theemergency call interval has expired, then the rescuer initiatedemergency notification sequence depicted in FIG. 4 is called in a block152 so that the rescuer is instructed to notify the emergency responsein the conventional manner.

It will be appreciated that the emergency response system notified byeither the rescuer or the device may be the public emergency responsesystem for local EMS such as police, fire, etc. or a private emergencyresponse system such as a private security or alarm monitoring system.Consequently, the AED 10 is preprogrammed with the appropriate telephonenumber for the desired emergency response system. In the United States,the public emergency response system is usually notified by calling 911.However, in some remote areas of the U.S. and in many foreign countriesdifferent telephone numbers are assigned to the local, public emergencyresponse system.

Finally, in yet other actual embodiments of the present invention, therescuer or device initiated emergency notification sequence may takeplace separately from the AED 10. For example, if the AED 10 is deployedfrom a docking station, the docking station could execute the emergencynotification sequence if it were equipped with the necessary hardwareand software.

Returning to FIG. 3, following initiation of the emergency notificationsequence in block 110, the AED 10 issues visual and aural instructionsto the rescuer to place the patient in a proper patient treatmentposition. For example, the visual instruction depicting properpositioning of the patient as shown in FIG. 10C is generated on thedisplay 14 of the AED 10. At the same time, the rescuer is providedverbal instructions via the speaker 18 to “Turn Victim to Their Back,while Supporting Their Head and Neck.” Next, in a block 114, a patientassessment sequence is initiated by the user interface program 22. Asnoted above, the rescuer may have pressed the start button 12 a singletime to proceed to the patient assessment sequence from the patientpositioning instruction. Although not depicted in FIG. 3, the rescuercan also repeat the patient positioning instruction (as well as anyother instruction provided by the user interface program 22) by pressingthe start button 12 twice. In addition, if the rescuer wishes todiscontinue operation of the AED 10 completely, the rescuer merelypresses the start button 12 and holds it for a predetermined time topower off the AED 10.

Returning to block 114, the rescuer is instructed to assess thepatient's condition once the patient has been placed in the appropriateposition. The patient assessment sequence is shown in more detail inFIG. 6. The logic in FIG. 6 begins in a block 160 and proceeds to ablock 162 where the user interface program 22 instructs the rescuer tocheck the patient's breathing. More specifically, a visual instructionto check the patient's breathing as shown in FIG. 10D is generated onthe display 14 of the AED 10, while the rescuer is verbally instructedvia the speaker 18 to “Tilt Head, Lift Chin” and “Look, Listen and Feelfor Breathing.” The rescuer is then provided a verbal instruction viathe speaker 18 as follows “If Breathing, Press Start Button Once toContinue.” Consequently, in decision 164 if it is determined that thepatient is breathing, i.e., if the start button has been pressed once,the logic proceeds to a decision block 166 where the user interfaceprogram 22 instructs the rescuer to place the patient in the recoveryposition. More specifically, a visual instruction as shown in FIG. 10Jis generated on the display 14 of the AED 10, while the rescuer isverbally instructed via the speaker 18 to “Roll Victim to Their Side IfBreathing” and “Stay with Victim Until Help Arrives.” Next, in a block168, the logic waits for a predetermined or x number of minutes, e.g.,two minutes, before returning to block 162 and reinitiating the patientassessment sequence.

Returning to decision block 164, if the rescuer does not indicate thatthe patient is breathing by pressing the start button 12 once, the logicwill proceed to a decision block 170 where it determines if the timeinterval for the rescuer to take action has expired or if the rescuerhas pressed the start button 12 two times to proceed to the nextinstruction. If neither of these conditions have been satisfied, blocks164 and 170 are repeated until either the rescuer indicates the patientis breathing or until the rescuer action interval expires or the rescuerpresses the start button 12 twice to proceed to the next instruction.

Upon expiration of the rescuer action interval or an indication from therescuer to continue to the next instruction, the logic proceeds to adecision block 172 where it determines if rescue breathing or CPRdelivery was just performed. If not, then it is necessary for the AED 10to instruct the user to deliver rescue breaths before continuingfurther. To determine whether rescue breathing or CPR delivery was justperformed, the user interface program 22 determines whether it haspreviously instructed the user to deliver rescue breaths as part of thepatient assessment sequence or if it has prompted the rescuer to deliverbreaths as part of a CPR delivery sequence (described in more detailbelow) immediately prior to prompting the rescuer to check the patient'sbreathing. If the result of decision block 172 is positive, the logicproceeds to a block 174 where the AED 10 instructs the rescuer todeliver a predetermined or y number of rescue breaths to the patientwhere y, for example, is the number of rescue breaths currentlyrecommended under a given standard protocol when a patient is notbreathing and a pulse check has not yet been conducted. In accordancewith the AHA HeartSaver CPR protocol for adult CPR delivery, this numberis presently two. As for generation of the appropriate instruction, themicroprocessor 24 of the AED 10 generates a visual instruction as shownin FIG. 10E on the display 14 of the AED 10 and simultaneously causesthe speaker 18 to issue a verbal instruction as follows: “If notbreathing, give two slow breaths. Tilt, head, lift chin, pinch nose.Blow. (Pause) Blow. (Pause).”

It will be appreciated by those of ordinary skill in the art thatfollowing each verbal instruction to “blow,” there will be a pause of anappropriate length of time before issuing the next verbal “blow”instruction so as to provide the rescuer with sufficient time to performthe instruction. Under the AHA HeartSaver CPR protocol this pause is 1.5to 2 seconds. Accordingly, the rescuer is guided to perform theinstructed task at appropriate time intervals. Alternatively, ratherthan repeating the verbal instruction to blow, the speaker 18 may repeatan audible tone at predetermined time intervals to assist the rescuer inexecuting the blow instruction. Further, the corresponding visualinstruction generated on the display 14 may be synchronized with theverbal instruction such that the visual instruction flashes at the sametime as the verbal instructions are repeated.

Returning to blocks 172 and 174, after rescue breathing has beenperformed, the logic proceeds to a block 176 where the rescuer isinstructed to check the patient's pulse. More specifically, the userinterface program 22 causes the microprocessor 24 to generate a visualinstruction to check the patient's pulse as shown in FIG. 10F on thedisplay 14 of the AED 10. Simultaneously, a verbal instruction is issuedvia the speaker 18 for the rescuer to “Check Pulse.” If the rescuerpresses the start button 12 to indicate that a pulse has been detected,the logic proceeds to a block 180 where the rescuer is instructed todeliver a predetermined or z number of rescue breaths to the patient,where z, for example, is the number of rescue breaths currentlyrecommended under a given standard protocol when a pulse is detected,but a patient is not breathing. In accordance with the current AHAHeartSaver CPR protocol, the appropriate number of rescue breaths to bedelivered when a pulse has not been detected is twelve. The userinterface program 22 instructs the microprocessor 24 to generate avisual instruction to deliver rescue breaths as shown in FIG. 10E on thedisplay 14 of the AED 10. A simultaneous verbal instruction is providedvia the speaker 18 as follows: “If Not Breathing, Give Twelve SlowBreaths. Tilt Head, Lift Chin, Pinch Nose. Blow. (Pause) Blow. (Pause)Blow . . . .” As noted above, a pause of a length appropriate to allowthe user to perform the blow instruction follows each such instruction.For example, under the AHA HeartSaver CPR protocol this pause is fiveseconds. Upon completion of the visual and verbal instruction to deliverrescue breathing, the logic of FIG. 6 returns to block 162 where thepatient assessment sequence is reinitiated and the rescuer is once againinstructed to check the patient's breathing.

Returning to decision block 178, if the rescuer does not indicate that apulse has been detected by pressing the start button 12, the logicproceeds to a decision block 182 where it determines if the rescueraction interval has expired or if the rescuer has pressed the startbutton 12 twice to continue to the next instruction. If the result ofdecision block 182 is negative, blocks 178 and 182 are repeated untileither a pulse has been detected by the rescuer or until the rescueraction interval has expired or the rescuer has proceeded to the nextinstruction. In the latter case, if the rescuer action interval expires,or if the rescuer proceeds to the next instruction, it is assumed that apulse has not been detected. Accordingly, the microprocessor 24 isinstructed to return in a block 184 to the main user interface program22 to a decision block 116 so that further instruction can be deliveredto the rescuer for operating the AED 10 and providing defibrillationtherapy to the patient, if necessary.

The user interface program 22 determines in decision block 116 if apredetermined or n number of total shocks have already been delivered tothe patient, where n is the number of total shocks currently recommendedunder a given standard protocol. Current standards vary geographicallyand according to associated medical direction. In some EMS systems, themaximum total number of shocks that may be given to a patient is nine.It will be appreciated, that if the maximum number of shocks havealready been delivered to the patient without resulting in successfulconversion of the patient's heart to a normal rhythm, that furtherdefibrillation therapy may be fruitless without ACLS intervention.Consequently, if the maximum total number of shocks has already beendelivered, the user interface program 22 will instruct the user todeliver CPR in a block 126 rather than repeat the AED operationsequence.

On the other hand, if a maximum total number of shocks has not alreadybeen delivered, the logic will proceed from decision block 116 todecision block 120 where the user interface program 22 determines if theelectrodes 16 of the AED 10 have been attached to the patient. It willbe appreciated that upon initial power-on of the AED 10, the rescuer maynot have already attached the electrodes 16 to the patient.Consequently, the AED 10 must instruct the rescuer to do so.Accordingly, the logic proceeds to a block 122 where an electrodeattachment sequence is initiated by the user interface program 22.However, if the electrodes have already been attached, the userinterface program 22 will skip the electrode attachment sequence andproceed directly to initiating an AED sequence for providingdefibrillation therapy in a block 124.

The logic implemented by the user interface program 22 to perform theelectrode attachment sequence is shown in more detail in FIG. 7. Thelogic of the electrode attachment sequence begins in a block 240 andproceeds to a block 242 where the microprocessor 24 generates the visualinstruction for electrode attachment shown in FIG. 10H on the display 14of the AED 10. Although not shown, if the electrodes 16 are sealedwithin an electrode package, an additional visual instruction may bedisplayed for the electrode package opening action. Simultaneously withthe visual instruction, a verbal instruction is issued via the speaker18 to “Apply Adhesive Pads to Bare Chest.” Once the instructions havebeen given for electrode attachment, the logic proceeds to a block 244where it determines if the electrodes have been properly attached to thepatient so that a proper connection between the electrodes and the AED10 has been established. If so, the AED 10 issues both visual and verbalinstructions via the display 14 and speaker 18, respectively, indicating“Adhesive Pads Connected” in a block 246. Next, in a block 248,processing returns to the main user interface program 22 at block 124where the AED sequence for operating the device to deliverdefibrillation therapy is initiated.

Returning to decision block 244, if a proper connection between thepatient, electrodes and AED 10 has not been established, the logicproceeds to a decision block 248 where it determines if a time intervalallowed for connecting the electrodes 16 to the patient has expired. Ifnot, decision blocks 244 and 248 are repeated until either a properelectrode connection has been established or the electrode connectioninterval expires. If the electrode connection interval expires withoutproper connection being established, the logic proceeds to a decisionblock 250 to determine if the electrode attachment sequence currentlybeing performed was interrupt driven due to detachment of the electrodesfrom the patient during treatment or if the electrode attachmentsequence is being implemented for the first time following deployment ofthe defibrillator and initial instructions to the rescuer to attach theelectrodes. If interrupt driven, it is likely that the electrodes havebecome detached during CPR delivery or perhaps during the AED sequence.Accordingly, it is prudent for the rescuer to reassess the patient'scondition and deliver CPR before attempting to reattach the electrodes.Accordingly, the logic proceeds from decision block 250 to a block 256where the patient assessment sequence is initiated to instruct therescuer to again assess the patient for breathing and pulse. Followingpatient assessment, the logic proceeds to a block 258 where a CPRdelivery sequence of instructions described in more detail below isprovided to the rescuer. Following patient assessment and CPR delivery,the logic of FIG. 7 returns to block 242 where the rescuer is againprovided instructions for attaching the electrodes 16 to the patient.

Returning to decision block 250, if the current electrode attachmentsequence was not interrupt driven, i.e., if the sequence was called fromthe main user interface program 22 in block 122, the logic proceeds fromdecision block 250 to a block 252 where the CPR delivery sequence isinitiated. It will be appreciated that since the electrode attachmentsequence was called in this instance for the first time after power-on,patient assessment has just been instructed. Therefore, CPR may bedelivered without reassessing the patient. However, following CPRdelivery, the patient assessment sequence is repeated in a block 254.The logic then returns to block 242 and the rescuer is instructed onceagain to attach the electrodes 16 to the patient. As is readily apparentfrom the above discussion, the electrode attachment sequence maycontinue indefinitely until proper connection of the electrodes 16 isestablished. Accordingly, the rescuer will be instructed repeatedly toassess the patient's condition and deliver CPR until emergencyassistance arrives.

As noted above, once proper connection of the electrodes 16 has beenestablished, the logic of the main user interface program 22 proceeds toa block 124 where an AED sequence is initiated which instructs therescuer in proper operation of the defibrillator so as to providedefibrillation therapy to the patient, if necessary. The logic of theAED sequence is shown in more detail in FIGS. 8A and 8B. The logicbegins in FIG. 8A in a block 190 and proceeds to a block 192 where anautomatic heart rhythm detection algorithm is activated and executed bythe microprocessor 24 based on the ECG signals received from theelectrodes 16.

Following activation of the automatic rhythm detection algorithm inblock 192, the AED 10 notifies the rescuer that analysis has begun andinstructs the rescuer to stand clear. More specifically, a visualinstruction to stand clear as shown in FIG. 10I is generated by themicroprocessor 24 on the display 14 of the AED 10. In addition, thefollowing verbal instruction is issued via the speaker 18: “AnalyzingPatient, Stand Clear. Do Not Touch Patient!” After the instruction hasbeen issued, the logic proceeds to a decision block 196 where itdetermines whether CPR should be delivered prior to any shock. It willbe appreciated that certain standard, accepted defibrillation protocolsadvise that CPR should be delivered before any defibrillation therapy.In the actual embodiment of the present invention described herein, theAED 10 is preprogrammed to require that CPR be delivered preceding ashock in accordance with such accepted protocols. Consequently, thelogic automatically proceeds from decision block 196 to a decision block198 where it determines if a predetermined or j number of CPR cycles CPRhas already been delivered to the patient by the rescuer, where j is thenumber of CPR cycles currently recommended under a given, standard CPRprotocol. Current standards vary according to medical direction. In someEMS systems six cycles or ninety seconds of CPR are delivered prior todefibrillation. In other words, the logic determines in decision block196 whether sufficient CPR has been delivered so that defibrillationtherapy may continue. If not, the logic proceeds to a block 202 whereprocessing returns to the main user interface program 22 at a block 126where the CPR delivery sequence of instructions is initiated.

Returning to decision block 196, in another actual embodiment of thepresent invention, the automatic rhythm detection algorithm is designedto automatically advise delivery of CPR preceding a shock. If so, theAED sequence will skip the determination of whether a sufficient numberof cycles of CPR has been delivered and instead proceed directly toblock 202 so processing may resume in the main user interface program 22with delivery of CPR instructions in a block 126.

Returning to decision block 198, if the appropriate number of CPR cycleshas already been delivered, the logic proceeds to a decision block 200and continues with the AED sequence so that defibrillation therapy maybe delivered if necessary. In decision block 200, the logic decideswhether a predetermined or n number of consecutive shocks have alreadybeen delivered to the patient. Again, in accordance with the current AHAguidelines the maximum number of consecutive shocks allowed is three. Ifa maximum number of shocks has been delivered consecutively withoutsuccessful conversion of the patient's heart to a normal heart rhythm,defibrillation therapy will not continue. Rather, processing will returnin a block 202 to the main user interface routine so that CPR deliverycan be instructed to the user in a block 126. However, if the maximumnumber of consecutive shocks has not yet been reached, the logic willproceed in FIG. 8A from decision block 200 to a decision block 204 whereit determines whether or not the automatic rhythm detection algorithmhas detected a shockable rhythm. As those of ordinary skill in the artwill recognize, not all abnormal heart rhythms are treatable bydefibrillation therapy. However, CPR may still be of benefit to thepatient. Accordingly, if a shockable rhythm is not detected, processingwill return in block 202 to the main user interface program 22 so thatthe CPR delivery sequence of instructions may be initiated in a block126.

On the other hand, if a shockable rhythm is detected in decision block204, the logic proceeds to a block 205 in which the AED instructs theuser verbally that “Shock Advised, Stand Clear.” In addition, themicroprocessor 24 generates a corresponding visual instruction such asthat shown in FIG. 10I on the display 14 of the AED 10. After therescuer is instructed that a shock has been advised and to stand clear,the AED 10 initiates charge of an energy storage component, e.g., acapacitor, for the device. As those of ordinary skill in the art willappreciate, charging may not be necessary at this point if the energystorage component was precharged and thus, was ready to deliver theshock immediately. However, in the actual embodiment of the presentinvention described herein, the energy storage component is not, infact, precharged. Therefore, in a block 208, the AED 10 instructs theuser both visually (in text format) and verbally that the energy storagecomponent is “Charging.” Next in a decision block 210, the logicdetermines whether the AED 10 is ready to deliver a defibrillationshock, i.e., whether the energy storage component is fully charged. Ifnot, blocks 208 and 210 are merely repeated until the energy storagecomponent has become fully charged.

Once the device is ready to shock, the logic proceeds to a block 212 onFIG. 8B in which the rescuer is instructed to “Press Shock Button” inorder to trigger delivery of the defibrillation pulse to the patient.Further visual instruction to press the shock button are given to therescuer by causing the shock button 11 to flash repeatedly. In anotheractual embodiment of the present invention, the AED 10 is programmed todeliver the shock automatically without further rescuer intervention ifa shockable rhythm is detected and the energy storage component is fullycharged. In such embodiment, the AED 10 would not include a shock button11. Regardless of whether the rescuer presses the shock button 11 toinitiate the delivery of the defibrillation pulse or whether the AED 10is programmed to deliver the shock automatically, the logic proceedsfrom block 212 to a decision block 214 where it determines if the shockhas been delivered. If not, the logic proceeds to a decision block 216where it determines if the shock delivery interval has expired. If not,blocks 214 and 216 are repeated until the shock is either delivered (asinitiated by the rescuer pressing the shock button 11 or automaticallyby the AED 10) or until the shock delivery interval has expired. If theshock is delivered, the rescuer is instructed both verbally and visuallythat “Shock Delivered.” The logic then returns to block 192 on FIG. 8Ato reactivate the automatic rhythm detection to determine whether thepatient's heart has been converted to a normal rhythm.

If the shock delivery interval has expired before a defibrillation pulseis delivered to the patient, the logic proceeds to a decision block 220where it determines if the rescuer or AED 10 has had a predetermined ork number of chances to shock the patient. In the actual embodiment ofthe present invention described herein, the rescuer is given threeopportunities to shock the patient. If those three opportunities havenot yet been provided, the logic returns to block 192 of FIG. 8A so thatthe automatic rhythm detection algorithm can be reactivated and thepatient's heart rhythm analyzed once again. If the rescuer has had theacceptable number of opportunities to shock the patient but hasrefrained from doing so, processing returns to the main user interfaceprogram 22 in FIG. 3 at a block 126 so that the rescuer may beinstructed to deliver CPR to the patient.

Returning now to FIG. 3, after the patient's condition has been assessedby the rescuer, the rescuer has attached the defibrillation electrodes16 to the patient, and the patient's heart rhythm has been monitored fora shockable heart rhythm such as ventricular fibrillation, the logicproceeds to a block 126 where the CPR delivery sequence is initiated bythe user interface program 22. The CPR delivery sequence is shown inmore detail in FIG. 9. The logic in FIG. 9 begins in a block 230 andproceeds to a block 232 where the rescuer is instructed to deliver apredetermined or p number of chest compressions to the patient. Morespecifically, the visual instruction for delivering chest compressionshown in FIG. 10G is generated on the display 14 of the AED 10. In thepresent example, p is the number of compressions required under the AHACPR protocol for an adult, which is typically 15. In addition to thevisual instruction provided by the AED 10, a verbal instruction isprovided simultaneously via the speaker 18 to “Place Heel of Hand inMiddle of Chest Centered along Nipple Line. Press Firmly 15 Times.Press. (Pause) Press. (Pause) . . . . ” As discussed above, the pausesbetween verbal instructions to “Press” are of appropriate length for therescuer to perform the instruction. Under the AHA HeartSaver protocol,80 to 100 compressions per minute are recommended. Hence, the rescuermay synchronize his or her actions with the timed verbal instruction.

Once the rescuer has delivered the predetermined number of compressionsin block 232, the logic proceeds to a block 234 where the rescuer isinstructed to deliver q breaths to the patient, where y is apredetermined number of breaths preprogrammed into the user interfaceprogram 22. In the present example, q is the number of breaths requiredunder the AHA CPR protocol for an adult, typically two. The visualinstruction for delivery breaths generated by the microprocessor 24 onthe display 14 of the AED 10 is shown in FIG. 10E. A verbal instructionto “Tilt head, lift chin, pinch nose. Blow. (Pause) Blow. (Pause).” isthen provided simultaneously with the visual instruction shown in FIG.10E.

Next, in a decision block 236, the logic determines if a predeterminedor r number of CPR cycles has been delivered. In other words, the logicdetermines if blocks 232 and 234 been executed a predetermined number oftimes. In the actual embodiment of the present invention describedherein, r is the number of CPR cycles recommended under the AHA CPRprotocol for an adult, typically four. However, it will be appreciatedthat this number as well as any of the others mentioned above may varydepending on the protocol preprogrammed into the user interface program22. If the recommended number of CPR cycles has not been delivered,blocks 232, 234 and 236 are repeated until the appropriate number ofcycles has been delivered. At that point, processing returns in a block238 to the routine from which the CPR delivery sequence was called,e.g., user interface program 22, electrode attachment sequence, etc.Those of ordinary skill in the art will appreciate that in other actualembodiments of the present invention, an alternative test fordetermining when CPR has been sufficiently performed can be implementedin decision block 236. For example, block 236 may determine whether CPRhas been delivered for a predetermined time interval t. For example,under the AHA protocol for CPR for an adult, time t is one minute.

Returning to FIG. 3, once the CPR delivery sequence has been performedin block 126, the logic returns to block 116 and blocks 116-126 arerepeated indefinitely. Consequently, the user will continuously beinstructed to administer CPR and defibrillation therapy until emergencyservices arrive or until the device is powered down. It will beappreciated that power down could occur by loss of battery or AC powerto the AED 10 or by the rescuer pressing the start button 12continuously for a period of time long enough to distinguish such abutton press from a button press which would merely indicate that therescuer wishes to proceed to the next instruction. In yet otherembodiments, power down is achieved by pressing an “off” button.

While a number of actual embodiments of the present invention have beenillustrated and described, it will be appreciated that various changescan be made therein without departing from the spirit and scope of theinvention. For example, although the user interface program 22 depictedin FIG. 3 is described above in accordance with the actual embodiment ofthe AED 10 shown in FIG. 1 having an LCD display 14, it will beappreciated that the user interface program 22 may also be implementedby the alternative embodiment of the AED 10′ depicted in FIG. 1B withminimal changes. More specifically, rather than generate the appropriatevisual instruction on an LCD, visual instructions would be provided tothe user by illuminating the LED 15 appearing below the fixed visualinstruction 17 as appropriate.

In yet other embodiments of the present invention, the verbalinstructions provided to the rescuer simultaneously and insynchronization with the visual instructions could be repeatedperiodically until the rescuer proceeds to the next instruction.Consequently, the rescuer would continually receive each verbalinstruction until the next action is taken. In yet other embodiments,the rescuer could proceed to the next instruction by issuing a voicecommand to the AED 10 rather than by pressing a button. In suchembodiments, the AED 10 would be required to have installed a voicerecognition module and microphone as noted above. In yet otherembodiments of the present invention, the user interface program 22 canprompt the user to input information regarding the patient that wouldassist the user interface program in providing more patient specificinstructions to the rescuer. For example, the user interface program 22could generate visual and/or verbal instructions to enter informationvia the start button 12 to distinguish whether the patient is an adult,child, or infant. Accordingly, the number of chest compressions, rescuebreaths, etc. required during CPR delivery and/or the maximum number fortotal and consecutive shocks would change accordingly.

It will further be appreciated that the visual and aural instructionsprovided by the intuitive user interface of the present invention mayvary from those noted above and illustrated. For example, moreinformation and instruction may be provided to a lay person for clarityand to reduce anxiety. In addition, instructions may be provided withless medical jargon. Accordingly, an even more user friendly userinterface is provided. Those of ordinary skill in the art will alsorecognize that as accepted CPR and defibrillation protocols change,e.g., by adding, deleting or reordering instructions, the AED 10 may bereprogrammed with a simple software upgrade to the user interfaceprogram 22 to achieve compliance. For example, the AED 10 may bereprogrammed to add visual and/or aural instructions to unobstruct thepatient's airway. Finally, it will be appreciated that anydefibrillation device, e.g., a manual defibrillator, a semi-automaticdefibrillator or a fully automatic defibrillator, may be equipped withthe user interface of the present invention.

The invention claimed is:
 1. An automatic defibrillator comprising: astorage capacitor adapted to be charged; a discharge circuit; an auraloutput device communicably coupled to a processor; at least oneelectrode communicably coupled to the processor; a visual output devicecommunicably coupled to the processor; an input device communicablycoupled to the processor; wherein the processor is configured to executeinstructions that cause the defibrillator to be configured to: monitorECG signals through the at least one electrode; analyze the ECG signalsthrough the processor to detect a shockable heart rhythm; responsive todetecting a shockable heart rhythm, cause at least one of the aural andvisual output devices to deliver information that includes a prompt todeliver a response through the input device to prevent the initiation ofan emergency protocol; and responsive to an expiry of a predeterminedperiod of time to deliver the response, autonomously initiate theemergency protocol including: causing the discharge circuit to dischargethe charged storage capacitor through the electrodes, delivering adefibrillation pulse to the patient.
 2. The defibrillator of claim 1,wherein the emergency protocol further comprises delivering a subsequentdefibrillation pulse based on detecting a shockable heart rhythmsubsequent to delivering the at least one defibrillation pulse.
 3. Thedefibrillator of claim 1, wherein the input device comprises at leastone of a button configured to be actuated, or a microphone configuredfor receiving voice commands.
 4. The defibrillator of claim 2, whereinautonomously initiating the emergency protocol further comprisespreventing the delivery of defibrillating pulses after a thresholdnumber of defibrillating pulses has been delivered.
 5. The defibrillatorof claim 1, wherein autonomously initiating the emergency protocolcomprises contacting an emergency service.
 6. The defibrillator of claim5, wherein contacting an emergency service comprises establishing acommunication link with at least one intermediate device capable ofcontacting an emergency service.
 7. A method for operating an automaticdefibrillator, the defibrillator including at least one of an auraloutput device and a visual output device, communicably coupled with aprocessor, the processor communicably coupled with at least oneelectrode and an input device, the method comprising: monitoring ECGsignal data through the at least one electrode; analyzing the monitoredECG signal data through the processor; detecting a shockable heartrhythm in the ECG signal data; responsive to detecting a shockable heartrhythm, causing at least one of the visual output device and the auraloutput device to deliver a notification that a shockable heart rhythmhas been detected; providing information for operating the defibrillatorto alleviate the detected shockable heart rhythm, wherein theinformation includes a first prompt for a response to be deliveredthrough the input device within a time interval to prevent the deliveryof a defibrillation pulse; and where a response is not delivered withinthe time interval, automatically causing the defibrillation pulse to bedelivered to the electrodes.
 8. The method of claim 7, wherein the inputdevice comprises a microphone, and the response to be delivered throughthe input device comprises a voice command.
 9. The method of claim 7,further comprising issuing a cue to bystanders.
 10. The method of claim9, wherein the cue to bystanders comprises at least one of a command tostand clear of the patient, or to contact an emergency service.
 11. Anautomatic defibrillator comprising: a processor; at least one electrodecommunicably coupled to the processor; a visual output devicecommunicably coupled to the processor; an aural output devicecommunicably coupled to the processor; an input device communicablycoupled to the processor; a communication device communicably coupled tothe processor; wherein the processor is configured to executecomputer-executable instructions, the instructions configured to causethe defibrillator to be configured to: receive physiological datathrough the at least one electrode, the physiological data correspondingto a patient; analyze the physiological data to determine an eventrequiring a responsive action; responsive to the analyzed physiologicaldata, provide information through at least one of the visual and auraloutput devices to at least one of the patient or an entity separate fromthe patient, the information relating to the event requiring theresponsive action and including a prompt to deliver a response throughthe input device to prevent the initiation of an emergency protocol; andestablish a communication link with an emergency response system throughthe communication device, based on the absence of the responsive action.12. The automatic defibrillator of claim 11, wherein the input device isconfigured to receive data relating to at least one parameter of thepatient.
 13. The automatic defibrillator of claim 11, wherein the atleast one parameter of the patient comprises: language, age, weight, andresting heart rate.
 14. The automatic defibrillator of claim 12, whereinproviding information through at least one of the visual and auraloutput devices to an entity separate from the patient includes providinginformation based on the at least one parameter of the patient.
 15. Theautomatic defibrillator of claim 14, wherein at least a portion of theinformation relating to an operation of the defibrillator is deliveredin the patient's language.
 16. The automatic defibrillator of claim 11,wherein the input device is configured to receive data relating to oneor more environmental parameter.
 17. The automatic defibrillator ofclaim 16, wherein the data relating to one or more environmentalparameter includes at least one of ambient noise or ambient temperature.18. The automatic defibrillator of claim 17, wherein the informationrelating to an operation of the defibrillator delivered through theaural output device includes selecting a volume level for the auraloutput device exceeding a determined volume level for ambient noise. 19.The automatic defibrillator of claim 11, wherein the defibrillator isfurther configured to: provide information relating to an operation ofthe defibrillator through the aural output device; determine a periodduring which a response may be received; and where no response isreceived, provide information relating to an operation of thedefibrillator through the visual output device.
 20. The automaticdefibrillator of claim 11, wherein providing information through atleast one of the visual and aural output devices to an entity separatefrom the patient includes providing information including at least oneof text or graphics generated through the visual output device.
 21. Theautomatic defibrillator of claim 20, wherein at least a portion of theinformation provided through the visual output device is animated. 22.The automatic defibrillator of claim 11, wherein providing informationthrough at least one of the visual and aural output devices to an entityseparate from the patient includes providing information includingauditory signals generated through the aural output device.
 23. Theautomatic defibrillator of claim 22, wherein the information providedthrough the aural output device includes a prompt for a response to bedelivered.
 24. The automatic defibrillator of claim 23, wherein theinput device is configured to receive the response to be delivered. 25.The automatic defibrillator of claim 22, wherein the informationprovided through the aural output device indicates that thedefibrillator is awaiting a response a previously issued prompt.
 26. Theautomatic defibrillator of claim 22, wherein the information providedthrough the aural output device corresponds to at least one of apresence or quality of signals received the electrode.
 27. The automaticdefibrillator of claim 22, wherein the information provided through theaural output device corresponding to at least one of a presence orquality of signals received the electrode includes an identification ofa value of the electrode signal indicative of a dislodged electrode. 28.The automatic defibrillator of claim 22, wherein the auditory signalsprovided through the aural output device comprise an audible tone. 29.The automatic defibrillator of claim 28, wherein the audible tonecorresponds to an alarm.